33c
Manny is outside, you don't get him after you see Grandpa, though.
You spell it Manny Heffley.
at the heffley's house in greg's room there is an address book.touch it and then when you are done looking for manny in the school then go up the apartment.
In the box on the top enter "to beat wimpy wonderland" and it will tell you how to solve the whole island!
after you check the school for manny you go to the retirement home and go up then find 33c
after you see him at the grandpa's house at the leisure towers building manny disappears until you help the guy with the snowplow truck
Manny Heffley
Greg's dad-Frank Heffley Greg's Mum-Susan Heffley Greg's big brother-Rodick Heffrey Greg's little brother- Manny Heffley
cheaky and very annoying
After you chase Manny from Rowley's house to the school, and then out of the school, you can continue right to Leisure Towers. You need the address book from Greg's house, which shows Grandpa Heffley's apartment number, 33-C. Climb up the outside and enter his window (if you stay way to the right, most objects will miss you).
You then go see the grandpa at Lesure Towers and talk to him and he will make u eat some salad and then he will tell you where he saw Manny
Greg Heffley's best friend is Rowley Jefferson.